Biggest difference is the economy. No communism, and instead of overdrive you have dedicated metal-makers (like a Mex, but powered entirely by energy and doesn't require placement on a metal spot). ZK punishes excessive economy by place diminishing returns on mex output with overdrive. TA rewards massive economies because the faster you can build fusions, the faster you can build metal makers, which means more fusions.... etc.... until you have +1000 metal income.
Static defenses are incredibly powerful in TA.
There are no Caretakers or Nano Turrets, so you have to build like 100 constructions planes set to patrol over your base to build stuff quickly.
Starts in TA are a bit more like SC where you start with little income and have to build your first factory, build construction units, etc.
It's generally a bit slower paced than ZK.